Elderly nursing home residents are frequently faced with decisions about major surgery. Realistic information about operative mortality and post-discharge treatment intensity is imperative to surgical decision making. Treating physicians, both gerontologists and surgeons, need information about expected outcomes in order to know when to refer a patient for surgery and when it is appropriate to operate on a frail elderly patient. Nursing home patients and their families also need information to make informed decisions about whether to proceed with surgery. However, informed decision-making is challenging given the limited information about how advanced age and frailty affect the risks of surgery. Moreover, the impact of major surgery on the cognitive and functional health status of nursing home residents is not well understood. To address these gaps, our project has three specific aims: Aim I. To describe outcomes after major surgery in the frailest elderly. Linking national Medicare claims data (1999-2004) to longitudinal data from the national Minimum Data Set for Nursing Homes (MDS, 1999- 2005), we will examine clinical outcomes in nursing home patients undergoing major elective and emergent surgery. Outcomes will include mortality, complications, duration of ICU stay, hospital length of stay, and hospital readmission. Aim II. To assess the effects of surgery on patients'cognitive and functional status. Using the same data sources, we will examine the effects of major surgery on cognitive ability and functional status among elderly nursing home residents. Aim III. To better predict surgical outcomes in nursing home patients. Using multivariate analysis, we will evaluate how patients'age, medical comorbidities, preoperative functional status and cognitive function influence outcomes after surgery in nursing home patients. We will also assess the interaction of these patient characteristics. Through these three aims, we will provide nursing home residents and their caregivers with much needed information about functional and clinical outcomes after major surgery.